1. Field of the Invention
The present invention relates to an electronic apparatus having a plurality of built-in functional blocks or units, and to a manufacturing method for the same.
2. Description of the Related Art
Multiple functional blocks or units have been built into electronic devices such as cards (individual circuit boards) that fit into expansion slots in PCs (personal computers) and integrated circuit (IC) devices. These devices have built-in multiple functional blocks or units such as DRAM (dynamic random access memory), flash ROM (read-only memory), or an ASIC (application specific integrated circuit). In order to use the DRAM or other numerous functions of the IC, card or other device, numerous input/output terminals are required on the IC, card or other device.
The present invention addresses the problems described above, and an object of this invention is to provide an electronic apparatus whereby only those internally provided functions that are needed can be selectively assigned to input/output terminals, thereby reducing the number of input/output terminals, improving reliability, and maintaining low cost, and to provide a method of manufacturing this electronic apparatus.
To achieve this object, an electronic apparatus according to a first aspect of the present invention is comprises a connection means or connector for connecting to an external circuit or external device; one or more functional blocks or units for executing a specific function; a switching circuit for selectively connecting a functional block to the connection means or connector; function selection terminals connected to the switching circuit for outputting to the switching circuit a signal specifying which functional block to connect to the connection means; and a signal determination means or unit for determining the signal output from the function selection terminal.
The switching circuit here can be configured to switch the functional block connected to the connection means based on change in an electrical characteristic or optical characteristic between the function selection terminals.
Furthermore, the instruction can be given to the switching circuit by applying to the function selection terminals a member that changes the characteristic between the function selection terminals, and an identification pattern indicating what functional block is connected to the connection means can be written on this member. This member can be a label, and the identification pattern written on the member can be letters or a bar code.
Furthermore, to resolve the above problem, an electronic apparatus according to a second aspect of this invention is comprises a connection means or connector for connecting to an external circuit or external device; one or more functional blocks or units for executing a specific function; a switching circuit for selectively connecting a functional block to the connection means; and a switching data storage means, storage or memory connected to the switching circuit for storing information and for outputting to the switching circuit a signal specifying which functional block to connect to the connection means.
The switching data storage means or memory is preferably rewritable. In addition, the switching data storage means can be Programmable Logic Array (PLA).
Furthermore, to resolve the above problem a method of manufacturing an electronic apparatus according to the first aspect of the invention is characterized by (a) a step for producing one or more functional blocks or units for executing a specific function; (b) a step for producing a connector that connects to an external circuit or external device; (c) a step for producing lines connecting the connector to all functional blocks or units; and (d) a step for cutting the lines connecting the connector to functional blocks or units that are unnecessary.
In this method, step (c) can produce the lines using semiconductor elements, and step (d) cuts the lines by destroying the semiconductor elements.
Furthermore, step (c) can form the lines so that the pattern of lines cut by step (d) forms a readable identification pattern. This identification pattern can be letters or a bar code.
Furthermore, step (d) can cut the lines with a laser.
To resolve the above problems, a manufacturing method for an electronic apparatus according to the second aspect of the invention is characterized by: (a) producing one or more functional blocks or units for executing a specific function; (b) producing a switching circuit that selectively connects a functional block to a connector that connects to an external circuit or external device; (c) producing a phase change unit from a phase change material; (d) producing a phase change detecto connected to the switching circuit for detecting a phase change of the phase change unit and outputting a detection signal to the switching circuit; and (e) changing the phase of the phase change unit so that a required functional block of the functional blocks or units and the connector are connected by the switching circuit.
In this case step (c) can produce the phase change unit from a material that changes from a crystalline phase to an amorphous phase.
In addition, step (e) can change the phase of the phase change unit by laser beam emission, or can change the phase of the phase change unit by a thermal head.
Furthermore, step (c) can make the phase change unit from a material that changes from a crystalline phase to an isotropic liquid phase.
Furthermore, step (c) can make the phase change unit from a material whereby phase change causes a change in dielectric constant; and step (d) produces the phase change detector from electrodes with the phase change unit disposed therebetween, a voltage applying unit that applies a voltage between the electrodes, and a voltage rise detection circuit that detects a voltage rise between the electrodes.
Furthermore, step (c) can produce the phase change unit so that the phase change pattern resulting from step (e) is a readable identification pattern. The identification pattern in this case can be letters or a bar code.
By selectively connecting a plurality of functional blocks or units to a connector and selecting the connections so that the necessary functional blocks or units are connected to the connector, numerous functions can be selectively used with few connections to an external device.